Aids has been one nightmare too many for Africa: the region is not coping with the pandemic. This marvellous book combines technical expertise with a worm’s-eye view of what is really happening, all delivered with an understated compassion. Its core is a devastating critique of the West’s Aids programmes, which Helen Epstein reveals to be the triumph of rival ideologies over evidence. These opposing principles have fought each other for the $4 billion annual funding now being poured into Aids, and, in the process, have diverted attention from more practical approaches.

Epstein is a young scientist who went to Africa in 1993 to test an Aids vaccine. The vaccine didn’t work: the disease is probably too complicated to be countered in this way. But gradually, Epstein raised her gaze from test tubes to the societies in which Aids was spreading at rates wholly outside the range of experience elsewhere.

Why was it spreading so fast in eastern and southern Africa? Epstein’s explanation sounds convincing and is straightforward. The region combines two practices that greatly increase HIV transmission. Boys are not circumcised, increasing the risk of infection. Informal polygamy is common, with much of the population maintaining a few stable coterminous relationships. Many people are thereby linked into a single network. We now know that HIV is transmitted predominantly in the first weeks after it is caught. If anyone in the network becomes infected through casual sex then the whole network rapidly contracts it. In contrast, serial infidelity, as common in our own society, yields much lower transmission rates. If one spouse gets infected, so will the other, but by the time they sleep with others they are less infectious.

What are the implications for Aids policy? Some behavioural modification is evidently essential, otherwise infection rates explode. But what modifications are critical and realistic? Well, Africans themselves came up with the answer: if you live in an informally polygamous society then it is literally vital not to sleep around or use prostitutes. In 1986, President Museveni of Uganda led a hard-hitting campaign with this message, brilliantly captured by the slogan “Zero Grazing”. It worked: the incidence of HIV declined precipitously as the campaign ran. We know it did, because two comparable and detailed surveys span its duration and show the decline and its explanation: people stopped sleeping around. We are aware of this now, partly thanks to Epstein, but we could have known it a decade ago when it happened. The reason it took so long is part of a staggering story, which explains why the Zero Grazing campaign was phased out in the early 1990s.

It didn’t fit the ideological left at the United Nations or the Christian right in America.

The UN wanted condoms and antiretrovirals. The Christians wanted chastity followed by fidelity. The UN hated Zero Grazing because it implied that people should show a degree of sexual restraint. The Christian right hated it because it didn’t imply sufficient restraint. During the 1990s, antiAids funding spiralled but it was channelled through the UN, and these days vast sums also go through the American government. Zero Grazing, and similar approaches that worked by fostering good sense and a recognition of the huge dangers involved in casual sex, were not just ignored, they were crushed by the weight of money going to other, far less effective approaches.

The biases from rival western ideologies were compounded by those of African leaders, with Museveni the heroic exception. President Mbeki of South Africa was so bound up with the imagined demons of western oppression that he went into denial. But his behaviour seems innocuous compared with that of senior health officials from various countries who siphoned off Aids funds on a grand scale. Take Zambia, one of the better-governed countries of Africa (which is why a particularly blatant scam has come to light). The permanent secretary of the Ministry of Health set up his own company to import useless drugs from Bulgaria and then got his ministry to buy them off his company. Or how about the South African NGO, supposedly helping orphans, that spent two-thirds of its $1.5m on building contracts? Or the $53m from the Global Fund that was plundered by Ugandan officials?

A tidal wave of international money may have been directed at the problem of Aids in Africa, but inadequate supervision and policies that are driven by ideology rather than evidence not only lead to wastage, but tempt badly paid officials into cynicism and from there to criminality. Unfortunately, so inadequate are the media in Africa that it is possible for leaders to fool most of the people most of the time. I doubt that Epstein would be surprised to learn that the latest Afro-barometer survey of citizen opinion finds a 70% approval rate of governments’ performance at combating Aids.

The UN and President Bush should not just read Epstein’s book, they should distribute it around Africa.

Off the scale

The scale of the Aids problem in southern and eastern Africa is breathtaking. The region, for instance, contains just 3% of the world’s population, but accounted in 2005 for nearly 40% of all HIV cases. In countries such as Botswana, Lesotho, South Africa and Swaziland, roughly a third of adults are now infected, a rate 10 times higher than anywhere else in the world outside Africa. Circumcision remains a vital weapon in combating the disease: one 2006 study showed that the practice could reduce the risk of HIV transmission by some 50%.

The invisible cure: Africa, the West and the Fight Against Aids by Helen Epstein
Viking £16.99 pp352

Buy the book here at the offer price of £15.29 (including p&p)

Paul Collier is the author of The Bottom Billion: Why the Poorest Countries Are Failing and What Can Be Done About It

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